MHD waves in the L-2 stellarator with ohmic heating

Experimental results on the fluctuations of the poloidal magnetic field during ohmic heating of the plasma in the L-2 stellerator are discussed. Kink modes were studied by correlation analysis of signals from magnetic probes. The presence of a region with l> or =1 at the periphery of the plasma column does not drive an m = 1, n = 1 instability. The experiments show that waves with high mode indices (m/n = 4/3, 5/4, and 6/5) grow at the periphery. The dependence of these modes on the ratio I/sub p//B/sub T/ and the size of the plasma column is studied. The experimental data agree well with theoretical predictions.